1. Field of Application
The present invention relates to a vehicle occupant detection apparatus for judging the status of a vehicle occupant who is seated in a seat of a vehicle, and for transmitting the results of the judgement to a vehicle occupant protection apparatus.
2. Description of Prior Art
In the prior art, a type of vehicle occupant protection apparatus has been proposed which is configured of a sensor formed of an electromechanical switch for detecting the presence or absence of a vehicle occupant in a seat of a vehicle, and a signal generating section that is provided within the sensor unit, for transmitting a coded signal indicative of the vehicle occupant presence or absence via a communication line to an air bag deployment apparatus.
Furthermore a vehicle occupant detection apparatus has recently been proposed whereby the loads imposed on a vehicle seat are measured at a plurality of locations by a plurality of strain gage load sensors that are mounted on the seat rails, i.e., for thereby measuring the weight of the individual who is occupying the seat. The objective is to enable the apparatus to not merely determine the presence or absence of a person in the seat concerned, but also to judge the type of vehicle occupant in that seat, i.e., to judge whether the person is adult, child, etc.
However with such a type of apparatus which judges the type of seat occupant by means of a plurality of strain gage load sensors, in order to be able to transmit the results of judgement of the seat occupant to an air bag deployment apparatus in the form of encoded data, it is necessary to provide the air bag deployment apparatus with a number of data input ports that is equal to the number of strain gage load sensors. Hence, a CPU that is used as a control section of the air bag deployment apparatus will be high in cost, while in addition each of the load sensors will be large in scale, making it difficult to mount these on the seat rails.